I ran this bot overnight after figuring out you have to split your funds between fiat and coins (I'd like coins only, not wait for the buy order and sell order to both fill). Even though there was not a single order placed at a loss, I ended up losing a good amount of money because about 25% of the orders placed were market orders, even with "post only" ticked.

Where is this happening? Because there is a difference between market making and market making. Officially market making describes 2 things. It describes making the spread smaller (like we do with the market making bot) or it can describe a situation where order should be placed in the orderbook and where it is not setup to be filled quickly (this last one is known as "post only").